{"id":"CVE-2026-56356","sourceIdentifier":"disclosure@vulncheck.com","published":"2026-06-30T23:17:30.997","lastModified":"2026-07-02T19:38:43.680","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"n8n contains a stored cross-site scripting vulnerability in the Chat Trigger node's Custom CSS field due to a misconfiguration of the sanitize-html library. Affected releases are those before 1.123.27, the 2.0.0 through 2.13.2 line, and 2.14.0 (fixed in 1.123.27, 2.13.3, and 2.14.1). An authenticated user with permission to create or modify workflows can inject JavaScript that bypasses sanitization, resulting in stored XSS against any user who visits the public chat page."}],"affected":[{"source":"disclosure@vulncheck.com","affectedData":[{"vendor":"n8n","product":"n8n","defaultStatus":"unaffected","packageURL":"pkg:npm/n8n","versions":[{"version":"0","lessThan":"1.123.27","versionType":"semver","status":"affected"},{"version":"1.123.27","versionType":"semver","status":"unaffected"},{"version":"2.0.0-rc.0","lessThan":"2.13.3","versionType":"semver","status":"affected"},{"version":"2.13.3","versionType":"semver","status":"unaffected"},{"version":"2.14.0","lessThan":"2.14.1","versionType":"semver","status":"affected"},{"version":"2.14.1","versionType":"semver","status":"unaffected"}]},{"vendor":"n8n","product":"n8n","defaultStatus":"unaffected","packageURL":"pkg:npm/n8n","versions":[{"version":"0","lessThan":"2.14.1","versionType":"semver","status":"affected"},{"version":"2.14.1","versionType":"semver","status":"unaffected"}]},{"vendor":"n8n","product":"n8n","defaultStatus":"unaffected","packageURL":"pkg:npm/n8n","versions":[{"version":"0","lessThan":"2.13.3","versionType":"semver","status":"affected"},{"version":"2.13.3","versionType":"semver","status":"unaffected"}]}]}],"metrics":{"cvssMetricV40":[{"source":"disclosure@vulncheck.com","type":"Secondary","cvssData":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","baseScore":5.1,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"LOW","userInteraction":"PASSIVE","vulnConfidentialityImpact":"LOW","vulnIntegrityImpact":"LOW","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"LOW","subIntegrityImpact":"LOW","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}}],"cvssMetricV31":[{"source":"disclosure@vulncheck.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","baseScore":5.4,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"REQUIRED","scope":"CHANGED","confidentialityImpact":"LOW","integrityImpact":"LOW","availabilityImpact":"NONE"},"exploitabilityScore":2.3,"impactScore":2.7}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-07-01T13:24:24.754142Z","id":"CVE-2026-56356","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"disclosure@vulncheck.com","type":"Secondary","description":[{"lang":"en","value":"CWE-79"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:n8n:n8n:*:*:*:*:*:node.js:*:*","versionEndExcluding":"1.123.27","matchCriteriaId":"C5E7FBA6-35F5-426D-8BAA-25C7913A966A"},{"vulnerable":true,"criteria":"cpe:2.3:a:n8n:n8n:*:*:*:*:*:node.js:*:*","versionStartIncluding":"2.0.0","versionEndExcluding":"2.13.3","matchCriteriaId":"8ACE2AF2-6C9A-41A8-9883-6F2149E24151"},{"vulnerable":true,"criteria":"cpe:2.3:a:n8n:n8n:2.14.0:*:*:*:*:node.js:*:*","matchCriteriaId":"22BDDF0A-0915-4FF2-920C-E75F2F2F677D"}]}]}],"references":[{"url":"https://github.com/n8n-io/n8n/security/advisories/GHSA-3c7f-5hgj-h279","source":"disclosure@vulncheck.com","tags":["Mitigation","Vendor Advisory"]},{"url":"https://www.vulncheck.com/advisories/n8n-stored-cross-site-scripting-in-chat-trigger-node-custom-css-field","source":"disclosure@vulncheck.com","tags":["Third Party Advisory"]}]}